A memory system may include a memory device storing data and a host controlling the memory device. The memory device may be volatile or nonvolatile. Volatile memory devices may include DRAM, SRAM, and the like. Nonvolatile memory devices may include EEPROM, FRAM, PRAM, MRAM, flash memory, and the like. Data stored in a volatile memory device may be lost at power-off. On the other hand, data stored at a nonvolatile memory device may be kept even at power-off.
In a memory system, a part of a disk may be used as a virtual memory to overcome limits in a physical memory capacity when a process is executed. A page required for execution of a current process may be first loaded onto a physical memory of a memory system using a page swap technique. Although loaded on the physical memory, a page judged to be currently unnecessary may be swapped out to a virtual memory. When execution on the swapped-out page is required later, the swapped-out page may be swapped into the physical memory from the virtual memory.